(Press-News.org) The workings of the ultrasonic warning sounds produced by the wings of a species of moth have been revealed by researchers at the University of Bristol.
Scientists recently discovered that moths of the genus Yponomeuta (so-called ermine moths) have evolved a very special acoustic defence mechanism against their echolocating predators—bats.
Ermine moths produce ultrasonic clicking sounds twice per wingbeat cycle using a minute corrugated membrane in their hindwing. Strikingly, these moths lack hearing organs and are therefore not aware of their unique defence mechanism, nor do they have the capability to control it using muscular action.
In the study, published today in Proceedings of the National Academy of Sciences, an interdisciplinary team of engineers and biologists from Bristol show how individual ridges of a corrugated patch in the hindwings of ermine moths snap-through because of in-flight wing folding. The sudden snap-through of these features vibrates an adjacent membrane, significantly amplifying the strength and direction of the produced sound. Owing to its passive in-flight actuation, this sound-producing organ is known as an ‘aeroelastic tymbal’.
Marc Holderied, Professor of Sensory Biology at the School of Biological Sciences, explained: “Our goal in this research was to understand how the corrugations in these tymbals can buckle and snap through in a choreographed way to produce a chain of broadband clicks. With this study, we unfolded the biomechanics that triggers the buckling sequence and shed light on how the clicking sounds are emitted through tymbal resonance.”
The study’s first author, Hernaldo Mendoza Nava, who investigated the mechanics of the aeroelastic tymbal as a PhD student at the EPSRC Centre for Doctoral Training in Advanced Composites for Innovation and Science of the Bristol Composites Institute (BCI), said: "Sound production and radiation is linked to mechanical vibration, for example in the skin of a drum or a loudspeaker.
“In ermine moths, the snap-through buckling events act like drumbeats at the edge of a tymbal drum, exciting a much larger portion of the wing to vibrate and radiate sound. As a result, these millimetre-sized tymbals can produce ultrasounds at the equivalent level of a lively human conversation."
To uncover the mechanics of the aeroelastic tymbal, Hernando combined state-of-the-art techniques from biology and engineering mechanics. The biological characterisation of the wing’s morphology and material properties ultimately led to detailed computer simulations of the snap-through response and sound production that match recorded moth signals in frequency, structure, amplitude, and direction.
Rainer Groh, Senior Lecturer in Digital Engineering of Structures at the BCI added: “The integration of various methods across the sciences with a consistent information flow across discipline boundaries in the spirit of ‘team science’ is what made this study unique and a success. In addition, without the amazing modern capabilities inimaging, data analysis and computation, uncovering the mechanics of this complex biological phenomenon would not have been possible."
The discovery will help researchers understand many other insect species with similar sound production mechanisms, filling a page of anti-bat acoustic defences in the book on the age-old arms race between echolocating bats and their insect prey.
Structural buckling and sound production are rarely studied together, despite being reciprocal phenomena. In addition, buckling occurs as a sudden large deformation which can be attractive as a shape-changing mechanism in the field of morphing structures, such as in the aerospace industry, where engineers are looking to optimise the aerodynamic performance of wings.
Alberto Pirrera, Professor of Nonlinear Structural Mechanics at the BCI, concluded: “In the realm of engineering design, nonlinear elastic responses, such as buckling and snap-through instabilities, have traditionally been perceived as failure modes to be avoided. In our research, we have been advocating a paradigm shift and have demonstrated that buckling events can be strategically leveraged to imbue structures with smart functionality or enhanced mass-efficiency. Yponomeuta’s aeroelastic tymbal embodies the concept of beneficial nonlinearity.
“The natural world, once again, serves as a source of inspiration.”
The research team anticipates that through bioinspiration, aeroelastic tymbals will encourage novel developments in the context of morphing structures, acoustic structural monitoring and soft robotics.
Paper:
‘Buckling-induced sound production in the aeroelastic tymbals of Yponomeuta’ by Hernaldo Mendoza Nava, Marc Holderied, Alberto Pirrera and Rainer Groh in Proceedings of the National Academy of Sciences of the USA.
END
A new analysis by MIT researchers shows the places in the U.S. where jobs are most linked to fossil fuels. The research could help policymakers better identify and support areas affected over time by a switch to renewable energy.
While many of the places most potentially affected have intensive drilling and mining operations, the study also measures how areas reliant on other industries, such as heavy manufacturing, could experience changes. The research examines the entire U.S. on a county-by-county level.
“Our result ...
THIS PRESS RELEASE IS EMBARGOED UNTIL FEBRUARY 5, 2024 at 3:00 PM U.S. EASTERN TIME
Many Indigenous peoples and local communities around the world are leading very satisfying lives despite having very little money. This is the conclusion of a study by the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB), which shows that many societies with very low monetary income have remarkably high levels of life satisfaction, comparable to those in wealthy countries.
Economic growth is often prescribed as a sure way of increasing the well-being of people in low-income countries, and ...
Many neurodegenerative diseases, including Alzheimer’s and Parkinson’s, are difficult to diagnose before symptoms begin to appear. However, disease-related biomarkers such as aggregated proteins called amyloids could provide important insight much earlier, if they can be readily detected. Researchers publishing in ACS Sensors have developed one such method using an array of sensor molecules that can light up amyloids. The tool could help monitor disease progression or distinguish between different ...
Janelia scientists and longtime collaborators Eric Betzig and Harald Hess will be inducted into the 2024 class of the National Inventors Hall of Fame for their invention of photoactivated localization microscopy (PALM), a pioneering imaging technology that enables scientists to image live cells in super-resolution to study biological structures and processes in unprecedented detail.
Betzig, a senior fellow at Janelia and an HHMI Investigator at the University of California, Berkeley, and Hess, a senior ...
Violence spreads in a contagious way like a disease among members of the Italian mafia, a new study shows.
Researchers have found committing violent acts with others increases the likelihood people in these groups will go on to carry out more violent offences in the future.
The analysis of the criminal careers of organised crime offenders shows previous violence has a “persistent and long-lasting” impact on their behaviour.
Prior violent co-offending has a greater impact than prior violent solo offending on the probability of future violence. Prior violent co-offending increases the probability ...
Petrina Kamya, PhD, Head of AI Platforms and President of Insilico Medicine Canada, will present at the BIO CEO & Investor Conference happening Feb. 26-27 at the New York Marriott Marquis in New York City. Dr. Kamya will speak as part of the panel “AI within Biopharma: Separating Value from Hype,” on Feb. 27, 1pm ET along with Michael Nally, CEO of Generate: Biomedicines and Liz Schwarzbach, PhD, CBO of BigHat Biosciences.
The session will look at how the latest artificial intelligence (AI) tools – including generative AI and large language models – ...
“[...] fruitful efforts to bring more drugs from bench to bedside could only be possible if we do not leave them ‘midway’!”
BUFFALO, NY- February 5, 2024 – A new editorial paper was published in Oncotarget's Volume 15 on January 24, 2024, entitled, “The fate of drug discovery in academia; dumping in the publication landfill?”
In this new editorial, researchers Uzma Saqib, Isaac S. Demaree, Alexander G. Obukhov, Mirza S. Baig, Amiram Ariel, and Krishnan Hajela, from Devi Ahilya Vishwavidyalaya, Indore, discuss drug discovery—a tedious process that is time consuming in both divulging whether a molecule is efficacious and specific in hitting ...
In a warming climate, meltwater from Antarctica is expected to contribute significantly to rising seas. For the most part, though, research has been focused on West Antarctica, in places like the Thwaites Glacier, which has seen significant melt in recent decades.
In a paper published Jan. 19 in Geophysical Research Letters, researchers at Stanford have shown that the Wilkes Subglacial Basin in East Antarctica, which holds enough ice to raise global sea levels by more than 10 feet, could be closer to runaway melting than anyone realized.
“There hasn’t been much analysis in this region – there’s huge ...
Gastrointestinal cancers (GCs) are among the most common forms of cancer and account for as much as one-third of all cancer deaths worldwide. Early diagnosis is an effective way of reducing the mortality associated with GCs, and endoscopic screening has proved to be an excellent approach for detecting potentially malignant tumors.
To extend the benefits of screening programs to as many people as possible, the imaging systems used should be inexpensive to manufacture and operate, yet accurate enough ...
Bariatric surgery is more effective in controlling hypertension rates, or high blood pressure, in people with obesity and uncontrolled high blood pressure compared to blood pressure medication alone, according to a study published today in the Journal of the American College of Cardiology. People who underwent bariatric surgery had lower BMI and were on fewer medications after five years while maintaining normal blood pressure levels than those who only used antihypertensive medications.
According to the CDC, the U.S. obesity and hypertension rates in adults are 41.9% and 45.4%, respectively. Obesity is a known ...